Accumulator-type fuel systems have an accumulator fuel volume for receiving fuel at high pressure and for delivering high pressure fuel to at least one of the injectors of the engine. Such systems are often referred to as common rail fuel systems and provide advantages for compression ignition internal combustion engines due to their flexibility and adaptability to engines of different type. Additionally, the pump requirement of the engine may be satisfied using just one high pressure fuel pump for supplying the common rail fuel volume, as opposed to an individual pump being required for each injector. The drive torque for common rail systems is also relatively low due to the ability to store energy within the rail fuel volume.
It is a disadvantage of common rail fuel systems that the common rail housing defining the rail volume occupies a large accommodation space within the engine. The rail housing is typically a forged part formed from steel and often must have relatively thick walls to withstand the high fuel pressures inside. The rail housing is therefore a relatively heavy and costly feature of the engine.
It is an object of the present invention to provide an accumulator fuel system which addresses the aforementioned problems.